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Sun, 07 Dec 2014 - The best meteor shower of the year

The Geminid meteor shower of 2014 is now underway.

The Geminids easily outperform the Perseids of August. Indeed, when you see the Geminids again after having been clouded out for a number of years, it can be a pleasant experience to be reminded as to just how good the Geminids actually are.

Being December, you do of course need to make sure that you wrap up well against the cold ... but the Geminids are worth it!

The 2014 Geminid peak is predicted during to occur during the late morning of Dec 14th. From the UK, the best rates are likely to be seen during the night of Dec 13-14 (Sat-Sun), although high rates are also likely to be seen during the nights of Dec 12-13 (Fri-Sat) and Dec 14-15 (Sun-Mon).

The peak ZHR for the Geminids usually exceeds 100 and exceeds 70 for about 24 hours. The ZHR is of course an hourly rate that would only be seen under ideal observing conditions. Observed rates will be lower when the Geminid radiant is low down in the sky, when the sky background is illuminated by moonlight or light pollution or if the sky is hazy. However, from a reasonable dark observing site with a good view of the sky, you may well see as many as 40 Geminids per hour when the radiant is high in the sky.

The Geminid radiant (the area of sky that Geminid meteors will appear to come from) lies close to the star Castor. It is above the horizon all night, but is low in the sky at first. Observed Geminid rates pick up as the evening progresses and from mid evening onwards good Geminid rates should be seen. The radiant is highest in the sky between 1am and 2am local time.

As always, avoid looking in the direction of the Geminid radiant itself. Any Geminids that appear close to the radiant will have short paths against the star background and will therefore be difficult to spot. To maximise the number of Geminids that you see, choose an area of sky that is around 30 degrees from the radiant and around 50 degrees above the horizon ... but do of course tailor this to take into account local factors such as sky obstructions and light pollution.

Observations of the early Geminids will be severely hindered by a bright gibbous Moon high in the sky. However, conditions become much more favourable as we approach the weekend of Dec 12-15, with Last Quarter occurring on Dec 14th. During the night of Dec 12-13, the Moon (on the Leo/Sextans border) will rise at around 22:20UT for observers in the UK. By the following night, Dec 13-14, with the Moon in Virgo, moonrise will be at around 23:25UT and during the night of Dec 14-15 the Moon will rise at around 00:30UT.

There is no need to stop observing when the Moon rises. If you do, you will be missing the period when the Geminid radiant is highest in the sky. Simply adjust the area of sky that you are observing to keep the Moon out of your field of view. If possible, observe from the shade of a building or trees to minimise any glare from moonlight being reflected from your surroundings.

The chart below shows the location of the Geminid radiant (in red):


















Alongside the Geminids, you will also see a number of sporadic meteors and maybe a late Taurid meteor - but do note that the Taurid radant location (as shown above) is somewhat different from that seen earlier in the shower.

Towards the end of the Geminid activity period, around Dec 16, you may also see an early member of the Ursid meteor shower.  


Added by: Tracie Heywood